The present invention relates to burners low in the generation of nitrogen oxides used in a small combustion apparatus for domestic or commercial.
Nitrogen oxides (NO.sub.x) in the exhaust gases from burners of various combustion devices are toxic by themselves and are believed to cause acid rain and photochemical smog. Various measures for decreasing the generation of No.sub.x in burners of combustion apparatus have been developed and utilized.
However, these measures are mainly directed to solving the problems of legally regulated large combustion apparatuses for industrial and other use. Such measures are not satisfactory for small combustion apparatuses for domestic or small commercial use because of noise and/or cost problems.
In a large combustion apparatus, the large static pressure produced by the combustion fan permits easy flow control of the combustion gas and air. This permits a high degree of freedom of layout, and easy noise control. So, with easy control of noise, and with large combustion chambers a possibility, slow combustion can be used to decrease No.sub.x emissions while still achieving perfect combustion. These advantages are not available in small combustion devices. It is therefore difficult to attain decreases in No.sub.x emissions comparable to that which are attainable in large combustion systems.